Seabed mining

Seabed mining (short- sea mining in the area of deep sea and deep seabed mining called) is mining , that is the prospecting , opening up and transporting of mineral raw materials ( mineral resources ) on and under the seabed .

Raw material deposits

Metallic raw materials (ores)

On and under the seabed, due to the different physical environment, there are significant deposits of some ores and polymetallic mineral aggregates made of metals, which occur only rarely in the earth's crust on land or mostly in low, non-mineable concentrations:

Ore sludge at plate edges
Cobalt-rich crust on deep-sea mountains and in areas with volcanic activity
Deep sea nodules :
- manganese
- Nickel , cobalt , copper
Iron in the coastal apron
Massive sulphides up to 3000 m depth
Heavy mineral soaps in shelf areas
Organic raw materials and phosphorite nodules up to a depth of 500 m

Gemstones

Off the coast of Namibia and South Africa, diamonds are extracted from the sediment bodies of rivers after they flow into the Atlantic, for example at Alexander Bay .

Fossil energy resources

The extraction of fossil raw materials for energetic as well as material utilization from the subsoil under the sea has been widespread for a long time .

oil
natural gas
Methane hydrate (so far hardly, but high future potential)

The deposits are usually developed using an oil rig or drilling ship , followed by extraction from the surface of the water using a production platform .

Bulk raw materials (stones and earth)

In shallow water near the coast, bulk raw materials such as sand or gravel are extracted with floating dredgers , which are mainly used as building materials .

Exploration of deep sea mining

In the international research program JPI Oceans , the pilot measure “Ecological Effects of Deep Sea Mining” is investigating whether the degradation of manganese nodules in the deep sea would endanger the species living there. Funded by the Federal Ministry of Education and Research , scientists from the Max Planck Institute for Marine Microbiology , the GEOMAR , the Alfred Wegener Institute , the MARUM and the Senckenberg Research Institute am Meer set out on a trip into the research ship SONNE in August 2015 Peru Basin in the Eastern Pacific. The aim of the scientists was to find out what ecological consequences the degradation of manganese nodules in the deep sea would have. The scientists found out that the previous communities in the regions where manganese nodules were removed no longer exist in the same species composition. The International Seabed Authority is responsible for the seabed outside the 200 nautical mile zone , where the scientists from the JPIO project presented their results in the summer of 2016 so that they can be incorporated into the regulations for deep-sea mining.

The subject of deep-sea resources, deep-sea mining and its ecological consequences was brought up by the Federal Ministry of Education and Research in 2015 in the G7 talks of science ministers. On the basis of the research results, it must be decided whether and how deep-sea mining can take place. The prerequisite are international standards that set the highest demands on how marine resources can be developed in an ecologically responsible manner.

environmental issues

Because of the enormous effort, marine mining is mainly carried out by high-tech industrialized countries, above all Japan. In order to work economically, deep-sea mining has to extract large quantities of ore: currently 5000 t of manganese nodules (wet) per day and per mining unit.

For every 5000 t of manganese nodules, at least 1 km² of the sea floor is degraded, which brings environmental problems :

mechanical destruction of the soil by mining equipment
Formation of a cloud of cloudiness, whereby organisms living in the soil (e.g. sponges ) are covered by sudden sedimentation
Disturbance of the biological balance in the deep sea due to mineral deprivation

literature

Henning Jessen: State responsibility and liability principles under international maritime law for environmental damage caused by deep-sea bottom mining. Journal for Environmental Law (ZUR) 02/2012, 71 ( PDF )
Sebastian Scholz: Raw material supply through marine mining. In: Ship & Harbor . Issue 5/2011, Seehafen-Verlag, Hamburg 2011, ISSN 0938-1643 , pp. 72-76.
Uwe Jenisch: Deep-sea mining in the pre-commercial phase. In: Ship & Harbor . Issue 11/2014, DVV Media Group, Hamburg 2014, ISSN 0938-1643 , pp. 36–39.
Peter E. Halbach, Andreas Jahn: Metals from the deep sea - promising source or illusion? In: Ship & Harbor . Issue 2/2015, pp. 36–41, DVV Media Group, Hamburg 2015, ISSN 0938-1643 .
Juergen B. Donges: The economics of deep-sea mining. Springer, Berlin 1985, ISBN 0-387-15144-3 .
Yves Fouquet et al .: Deep Marine Mineral Resources. Springer, Dordrecht 2014, ISBN 978-94-017-8562-4 .
Rahul Sharma: Deep-Sea Mining - Resource Potential, Technical and Environmental Considerations. Springer, Cham 2017, ISBN 978-3-319-52556-3 .